Basically it is a return line , or vent...Like Fred said, you can put an extension hose on it and a filter and just keep it in the back of the car....Ok question, this is similar to the fuel assembly in my tank. The fuel line is connected but this( circled in blue) is open with nothing on it, is it a vent and supposed to be open?
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More of the little beggars there today, enough for racing. From where I was sitting on that section of K-Rail just outside the catch fence, it looked like a good day to put the slicks on and save the treaded tires for a softer moister track. Kinda dusty it was and almost every racer spun out at least once during the heat races 
I had one of these.














